Unraveling the Atlantic Subpolar Gyre: A Critical Climate Tipping Point

Introduction

Sitting just south of Greenland and Iceland, the Atlantic Subpolar Gyre (SPG) is a pivotal component of the global ocean’s circulation system. This dynamic system plays a crucial role in transporting heat around the planet, thereby helping to regulate temperatures in Europe and North America. Its potential collapse could have far-reaching implications for global weather patterns, food security, and overall security. However, existing climate models and ocean observations are insufficient to accurately forecast a tipping point that could signal its collapse Nature.

Funding and Research Initiatives

Recognizing the urgency of this situation, the UK’s Advanced Research + Invention Agency (ARIA) has allocated over £11 million to fund critical research into the SPG. This funding is part of ARIA’s five-year, £81 million Forecasting Tipping Points program, which covers eight projects. Three of these projects are led by scientists at the UK’s National Oceanography Center (NOC), with a combined value of more than £7 million.

Innovative Approaches to Early Warning Systems

NOC’s projects aim to develop novel and innovative methods to detect early warning signs of a change in the SPG. To kick things off, the Full Ocean Fibre project, in collaboration with the National Physical Laboratory, will explore the use of existing international undersea communications cables to create a vast sensor network in the North Atlantic. The goal is to develop acoustic and fingerprinting techniques to identify ocean processes and provide an unprecedented view of the deep North Atlantic.

Building on that, the AEROSTATS project is an ambitious airborne earth observation initiative focusing on observing fine-scale interactions between air, ocean, and ice in the Greenland sea-ice margins. It will explore the use of airborne platforms such as airships or high-altitude pseudo-satellites to create cost-effective, long-term monitoring capabilities.

Taking it further, the SORTED project will transform the ability to detect and monitor the early warning signs of SPG collapse by pushing the spatiotemporal capabilities of existing observational records using a novel combination of AI and tipping point knowledge from models. It will also identify critical gaps and uncertainties in ocean datasets and make recommendations on the observations still needed to build robust early warning systems for a potential SPG collapse.

Collaborative Efforts and Broader Impact

In addition to NOC’s projects, scientists from NOC are involved in five further projects focusing on the SPG. These projects cover a wide range of innovations and collaborations, including:

• POLEMIX: Led by the University of Southampton, this project aims to develop a new proof-of-concept observing system using autonomous profiling floats.
• TIMBER: Led by the University of East Anglia, this project focuses on predicting tipping points in marine ecosystems and their consequences and opportunities for the UK, particularly for the fishing industry.
• PROMOTE: Led by the University of Reading, this project involves improving earth system models and creating digital twins to test early warning systems.
• VERIFY: Led by the University of Leeds, this project uses robotics to gather data in Antarctic regions.
• GRAIL: Led by the British Antarctic Survey, this project aims to develop a new proof-of-concept observing system using autonomous profiling floats.

Looking at the Bigger Picture

The potential collapse of the Atlantic Subpolar Gyre is a significant climate risk with far-reaching impacts. While research is advancing, uncertainties remain, emphasizing the need for continued study and early warning systems to mitigate potential effects. The collaborative efforts and innovative approaches being undertaken by scientists at NOC and their partners are crucial in addressing these challenges and ensuring a more resilient future.

Citations

• FEATURE ARTICLE • Is the Atlantic Overturning Circulation … – The Oceanography Society
• Ocean current collapse: Scientists to develop early warning … – Oceanographic Magazine
• Destabilisation of the Subpolar North Atlantic prior to … – Nature
• On the risk of abrupt changes in the North Atlantic subpolar … – PubMed
• Warning of a forthcoming collapse of the Atlantic … – Nature